4.3BSD-Reno/src/sys/kern/kern_ktrace.c
/*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* Redistribution is only permitted until one year after the first shipment
* of 4.4BSD by the Regents. Otherwise, redistribution and use in source and
* binary forms are permitted provided that: (1) source distributions retain
* this entire copyright notice and comment, and (2) distributions including
* binaries display the following acknowledgement: This product includes
* software developed by the University of California, Berkeley and its
* contributors'' in the documentation or other materials provided with the
* distribution and in all advertising materials mentioning features or use
* of this software. Neither the name of the University nor the names of
* its contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* @(#)kern_ktrace.c 7.9 (Berkeley) 6/28/90
*/
#ifdef KTRACE
#include "param.h"
#include "user.h"
#include "proc.h"
#include "file.h"
#include "vnode.h"
#include "ktrace.h"
#include "malloc.h"
#include "syscalls.c"
extern int nsysent;
extern char *syscallnames[];
int ktrace_nocheck = 0; /* set to 1 when security checks in place */
struct ktr_header *
ktrgetheader(type)
{
register struct ktr_header *kth;
MALLOC(kth, struct ktr_header *, sizeof (struct ktr_header),
M_TEMP, M_WAITOK);
kth->ktr_type = type;
microtime(&kth->ktr_time);
kth->ktr_pid = u.u_procp->p_pid;
bcopy(u.u_procp->p_comm, kth->ktr_comm, MAXCOMLEN);
return (kth);
}
ktrsyscall(vp, code, narg, args)
struct vnode *vp;
int code, narg, args[];
{
struct ktr_header *kth = ktrgetheader(KTR_SYSCALL);
struct ktr_syscall *ktp;
register len = sizeof(struct ktr_syscall) + (narg * sizeof(int));
int *argp, i;
if (kth == NULL)
return;
MALLOC(ktp, struct ktr_syscall *, len, M_TEMP, M_WAITOK);
ktp->ktr_code = code;
ktp->ktr_narg = narg;
argp = (int *)((char *)ktp + sizeof(struct ktr_syscall));
for (i = 0; i < narg; i++)
*argp++ = args[i];
kth->ktr_buf = (caddr_t)ktp;
kth->ktr_len = len;
ktrwrite(vp, kth);
FREE(ktp, M_TEMP);
FREE(kth, M_TEMP);
}
ktrsysret(vp, code, error, retval)
struct vnode *vp;
int code, error, retval;
{
struct ktr_header *kth = ktrgetheader(KTR_SYSRET);
struct ktr_sysret ktp;
if (kth == NULL)
return;
ktp.ktr_code = code;
ktp.ktr_error = error;
ktp.ktr_retval = retval; /* what about val2 ? */
kth->ktr_buf = (caddr_t)&ktp;
kth->ktr_len = sizeof(struct ktr_sysret);
ktrwrite(vp, kth);
FREE(kth, M_TEMP);
}
ktrnamei(vp, path)
struct vnode *vp;
char *path;
{
struct ktr_header *kth = ktrgetheader(KTR_NAMEI);
if (kth == NULL)
return;
kth->ktr_len = strlen(path);
kth->ktr_buf = path;
ktrwrite(vp, kth);
FREE(kth, M_TEMP);
}
ktrgenio(vp, fd, rw, iov, len, error)
struct vnode *vp;
int fd;
enum uio_rw rw;
register struct iovec *iov;
{
struct ktr_header *kth = ktrgetheader(KTR_GENIO);
register struct ktr_genio *ktp;
register caddr_t cp;
register int resid = len, cnt;
if (kth == NULL || error)
return;
MALLOC(ktp, struct ktr_genio *, sizeof(struct ktr_genio) + len,
M_TEMP, M_WAITOK);
ktp->ktr_fd = fd;
ktp->ktr_rw = rw;
cp = (caddr_t)((char *)ktp + sizeof (struct ktr_genio));
while (resid > 0) {
if ((cnt = iov->iov_len) > resid)
cnt = resid;
if (copyin(iov->iov_base, cp, (unsigned)cnt))
goto done;
cp += cnt;
resid -= cnt;
iov++;
}
kth->ktr_buf = (caddr_t)ktp;
kth->ktr_len = sizeof (struct ktr_genio) + len;
ktrwrite(vp, kth);
done:
FREE(kth, M_TEMP);
FREE(ktp, M_TEMP);
}
ktrpsig(vp, sig, action, mask, code)
struct vnode *vp;
sig_t action;
{
struct ktr_header *kth = ktrgetheader(KTR_PSIG);
struct ktr_psig kp;
if (kth == NULL)
return;
kp.signo = (char)sig;
kp.action = action;
kp.mask = mask;
kp.code = code;
kth->ktr_buf = (caddr_t)&kp;
kth->ktr_len = sizeof (struct ktr_psig);
ktrwrite(vp, kth);
FREE(kth, M_TEMP);
}
/* Interface and common routines */
/*
* ktrace system call
*/
/* ARGSUSED */
ktrace(curp, uap, retval)
struct proc *curp;
register struct args {
char *fname;
int ops;
int facs;
int pid;
} *uap;
int *retval;
{
register struct vnode *vp = NULL;
register struct nameidata *ndp = &u.u_nd;
register struct proc *p;
register ops = KTROP(uap->ops);
struct pgrp *pg;
register int facs = uap->facs;
register int ret = 0;
int error = 0;
/*
* Until security implications are thought through,
* limit tracing to root (unless ktrace_nocheck is set).
*/
if (!ktrace_nocheck && (error = suser(u.u_cred, &u.u_acflag)))
return (error);
if (ops != KTROP_CLEAR) {
/*
* an operation which requires a file argument.
*/
ndp->ni_segflg = UIO_USERSPACE;
ndp->ni_dirp = uap->fname;
if (error = vn_open(ndp, FREAD|FWRITE, 0))
return (error);
vp = ndp->ni_vp;
if (vp->v_type != VREG) {
vrele(vp);
return (EACCES);
}
}
/*
* Clear all uses of the tracefile
*/
if (ops == KTROP_CLEARFILE) {
for (p = allproc; p != NULL; p = p->p_nxt) {
if (p->p_tracep == vp) {
p->p_tracep = NULL;
p->p_traceflag = 0;
vrele(vp);
}
}
goto done;
}
/*
* need something to (un)trace
*/
if (!facs) {
error = EINVAL;
goto done;
}
/*
* doit
*/
if (uap->pid < 0) {
pg = pgfind(-uap->pid);
if (pg == NULL) {
error = ESRCH;
goto done;
}
for (p = pg->pg_mem; p != NULL; p = p->p_pgrpnxt)
if (uap->ops&KTRFLAG_DESCEND)
ret |= ktrsetchildren(p, ops, facs, vp);
else
ret |= ktrops(p, ops, facs, vp);
} else {
p = pfind(uap->pid);
if (p == NULL) {
error = ESRCH;
goto done;
}
if (ops&KTRFLAG_DESCEND)
ret |= ktrsetchildren(p, ops, facs, vp);
else
ret |= ktrops(p, ops, facs, vp);
}
if (!ret)
error = EPERM;
done:
if (vp != NULL)
vrele(vp);
return (error);
}
ktrops(p, ops, facs, vp)
struct proc *p;
struct vnode *vp;
{
if (u.u_uid && u.u_uid != p->p_uid)
return (0);
if (ops == KTROP_SET) {
if (p->p_tracep != vp) {
/*
* if trace file already in use, relinquish
*/
if (p->p_tracep != NULL)
vrele(p->p_tracep);
VREF(vp);
p->p_tracep = vp;
}
p->p_traceflag |= facs;
} else {
/* KTROP_CLEAR */
if (((p->p_traceflag &= ~facs) & ~KTRFAC_INHERIT) == 0) {
/* no more tracing */
p->p_traceflag = 0;
if (p->p_tracep != NULL) {
vrele(p->p_tracep);
p->p_tracep = NULL;
}
}
}
return 1;
}
ktrsetchildren(top, ops, facs, vp)
struct proc *top;
struct vnode *vp;
{
register struct proc *p;
register int ret = 0;
p = top;
for (;;) {
ret |= ktrops(p, ops, facs, vp);
/*
* If this process has children, descend to them next,
* otherwise do any siblings, and if done with this level,
* follow back up the tree (but not past top).
*/
if (p->p_cptr)
p = p->p_cptr;
else if (p == top)
return ret;
else if (p->p_osptr)
p = p->p_osptr;
else for (;;) {
p = p->p_pptr;
if (p == top)
return ret;
if (p->p_osptr) {
p = p->p_osptr;
break;
}
}
}
/*NOTREACHED*/
}
ktrwrite(vp, kth)
struct vnode *vp;
register struct ktr_header *kth;
{
struct uio auio;
struct iovec aiov[2];
struct proc *p;
int error;
if (vp == NULL)
return;
auio.uio_iov = &aiov[0];
auio.uio_offset = 0;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_rw = UIO_WRITE;
aiov[0].iov_base = (caddr_t)kth;
aiov[0].iov_len = sizeof(struct ktr_header);
auio.uio_resid = sizeof(struct ktr_header);
auio.uio_iovcnt = 1;
if (kth->ktr_len > 0) {
auio.uio_iovcnt++;
aiov[1].iov_base = kth->ktr_buf;
aiov[1].iov_len = kth->ktr_len;
auio.uio_resid += kth->ktr_len;
}
VOP_LOCK(vp);
error = VOP_WRITE(vp, &auio, IO_UNIT|IO_APPEND, u.u_cred);
VOP_UNLOCK(vp);
if (!error)
return;
/*
* If error encountered, give up tracing on this vnode.
*/
uprintf("\ntrace write failed with errno %d, tracing stopped\n", error);
for (p = allproc; p != NULL; p = p->p_nxt) {
if (p->p_tracep == vp) {
p->p_tracep = NULL;
p->p_traceflag = 0;
vrele(vp);
}
}
}
#endif